Clinical characteristics of acute non-varicose upper gastrointestinal bleeding and the effect of endoscopic hemostasis

BACKGROUND Acute non-variceal upper gastrointestinal bleeding(ANVUGIB)constitutes a prevalent emergency within Gastroenterology,encompassing 80%-90%of all gastrointestinal hemorrhage incidents.This condition is distinguished by its abrupt onset,swift progression,and notably elevated mortality rate.AIM To gather clinical data from patients with ANVUGIB at our hospital in order to elucidate the clinical characteristics specific to our institution and analyze the therapeutic effectiveness of endoscopic hemostasis.METHODS We retrospectively retrieved the records of 532 patients diagnosed with ANVUGIB by endoscopy at our hospital between March 2021 and March 2023,utilizing our medical record system.Data pertaining to general patient information,etiological factors,disease outcomes,and other relevant variables were meticulously collected and analyzed.RESULTS Among the 532 patients diagnosed with ANVUGIB,the male-to-female ratio was 2.91:1,with a higher prevalence among males.Notably,43.6%of patients presented with black stool as their primary complaint,while 27.4%had hematemesis as their initial symptom.Upon admission,17%of patients exhibited both hematemesis and black stool,while most ANVUGIB patients primarily complained of overt gastrointestinal bleeding.Urgent routine blood examinations at admission revealed that 75.8%of patients had anemia,with 63.4%experiencing moderate to severe anemia,and 1.5%having extremely severe anemia(hemoglobin<30 g/L).With regard to etiology,53.2%of patients experienced bleeding without a definitive trigger,24.2%had a history of using gastric mucosa-irritating medications,24.2%developed bleeding after alcohol consumption,2.8%attributed it to improper diet,1.7%to emotional excitement,and 2.3%to fatigue preceding the bleeding episode.Drug-induced ANVUGIB was more prevalent in the elderly than middle-aged and young individuals,while bleeding due to alcohol consumption showed the opposite trend.Additionally,diet-related bleeding was more common among the young age group compared to the middle-aged group.Gastrointestinal endoscopy identified peptic ulcers as the most frequent cause of ANVUGIB(73.3%),followed by gastrointestinal malignancies(10.9%),acute gastric mucous lesions(9.8%),and androgenic upper gastrointestinal bleeding(1.5%)among inpatients with ANVUGIB.Of the 532 patients with gastrointestinal bleeding,68 underwent endoscopic hemostasis,resulting in an endoscopic treatment rate of 12.8%,with a high immediate hemostasis success rate of 94.1%.

Analysis of the Current Situation of Drug Clinical Trial Institutions in Shaanxi Province

To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on the“Announcement on the Accreditation of Drug Clinical Trial Institutions”issued by the National Medical Products Administration from 2005 to August 2022,the record management information system of drug and medical device clinical trial institutions,and the drug clinical trial registration and information publicity platform.A retrospective analysis was carried out in terms of institutional development,regional distribution,registered majors,principal investigators,and the number of drug clinical trials.After the implementation of institution registration,the number of drug clinical trial institutions in Shaanxi Province increased by 47.4%,884 principal investigators were registered,the number of registered majors expanded from 58 qualified to 117,and the professional scope increased by 50.4%.The policy of institution registration is conducive to promoting the rational use of medical resources and the development of drug clinical trial institutions and improving the healthy development of the pharmaceutical industry in Shaanxi Province.

Clinical characteristics of myotonia congenita in China Literature analysis of the past 30 years

AIM： To understand the distinct, clinical features of myotonia congenita in China. METHODS： Case reports of myotonia congenita were retrieved from the Chinese Journal Full-text database, dating between 1980 and 2007, and analyzed for clinical characteristics of myotonia congenita. RESULTS： There were 35 published reports and 258 cases about myotonia congenita. Six reports （62 cases） were excluded due to lack of clinical data, imprecise diagnosis, or duplication. Finally, 29 published reports and 196 cases （140 males and 56 females） were included in this analysis. About 78.6% of patients were diagnosed with myotonia congenita before the age of 20, and among these, 86.1% were classified as dominant inheritance. Lower and upper extremities were frequently affected with severe symptoms. Eyelids, mouth and lingual muscles, and trunk muscles and cervical muscles were less frequently involved. However, muscles for swallowing, sphincter muscles, and smooth muscles were not involved. There were no reports of cataracts, cardiac conduction block, or dyscrinism. myotonia congenita symptoms were induced or aggravated by cold temperatures in 71.9% of the patients and warming-up effect occurred in 95.6% of the patients. Muscle hypertrophy was observed in 69.6% and percussion of muscles in 76.5% of the patients. Myotonia potential or myotonia-like potential was detected in all patients using electromyography. Muscle fiber swelling or hypertrophy was frequently detected through muscular biopsy. CONCLUSION： Myotonia congenita frequently occurs in males before the age of 20, in particular as the autosomal dominant form of myotonia congenita. Skeletal muscles throughout the body, especially the lower and upper extremities, are involved. However, muscles for swallowing, sphincter muscles, and smooth muscles are not involved. Warming-up effect is the main characteristic of myotonia congenita.

Analysis on the Variation Characteristics of Precipitation in North China during Recent 30 Years

Based on the monthly precipitation data from 43 stations in North China from 1979 to 2008,the variation characteristics of precipitation in North China in recent 30 years were analyzed by means of empirical orthogonal function(EOF)decomposition,Morlet wavelet transform and Mann-Kendall test.The results showed that the spatial distribution of annual and seasonal precipitation was basically identical in North China,while the annual and summer precipitation from the middle of 1980s to the middle of 1990s were obviously more than these in other periods,and there was great annual variation in spring precipitation in 1990s,while autumn precipitation was higher from 1980s to 1990s and then went down after the beginning of 21st century,which was opposite to winter precipitation,namely there was more winter precipitation from 1980s to 1990s and fewer winter precipitation after the beginning of 21st century.In addition,the annual and summer precipitation changed abruptly in 1997,and there was no obvious change in spring precipitation and autumn precipitation,while winter precipitation had an abrupt change in 2000.Meanwhile,wavelet analysis revealed that the variation period of annual and seasonal precipitation was 3-4 years.

Analysis of the Characteristics of Typical Haze in Winter

Based on meteorology and environment monitoring data in January,2008 in Liaoning central region,a typical haze weather process was analyzed.The results showed that haze was formed due to the stable weather condition in the earth surface and upper air layer in Liaoning central region.Especially because that the weakening of atmospheric dispersion ability in the urban boundary layer that was 500 m under earth surface,caused the pollutant in the air can not disperse.Thus,it resulted in the deterioration of air quality,increase of concentration of particulate mass,and declination of visibility.And in the end,haze formed.

The analysis of frequency-dependent characteristics for fluid detection: a physical model experiment

According to the Chapman multi-scale rock physical model, the seismic response characteristics vary for different fluid-saturated reservoirs. For class I AVO reservoirs and gas-saturation, the seismic response is a high-frequency bright spot as the amplitude energy shifts. However, it is a low-frequency shadow for the Class III AVO reservoirs saturated with hydrocarbons. In this paper, we verified the high-frequency bright spot results of Chapman for the Class I AVO response using the frequency-dependent analysis of a physical model dataset. The physical model is designed as inter-bedded thin sand and shale based on real field geology parameters. We observed two datasets using fixed offset and 2D geometry with different fluid- saturated conditions. Spectral and time-frequency analyses methods are applied to the seismic datasets to describe the response characteristics for gas-, water-, and oil-saturation. The results of physical model dataset processing and analysis indicate that reflection wave tuning and fluid-related dispersion are the main seismic response characteristic mechanisms. Additionally, the gas saturation model can be distinguished from water and oil saturation for Class I AVO utilizing the frequency-dependent abnormal characteristic. The frequency-dependent characteristic analysis of the physical model dataset verified the different spectral response characteristics corresponding to the different fluid-saturated models. Therefore, by careful analysis of real field seismic data, we can obtain the abnormal spectral characteristics induced by the fluid variation and implement fluid detection using seismic data directly.

The runoff characteristics and harmonic analysis of the soil moisture dynamics in Robinia pseudoacacia stand

Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the western Liaoning Province (1850-12225 E, 4024-4234 N) for measuring the characteristics of runoff and sediment as well as soil moisture dynamics. Contractive analysis of the two land types showed that there existed a significant difference in volumes of runoff and sediment between the sites of R. pseudoacacia stand and its clearcut area. The runoff volume and sediment volume in clearcut area were much bigger than those in R. pseudoacacia stand, with an increase amount of 40%-177% for runoff and 180%-400% for sediment. Hydrograph of surface runoff of typical rainfall showed that the peak value of runoff in R. pseudoacacia stand was decreased by 1.0-2.5?0-3m3s-1 compared with that in its clearcut area, and the occurring time of peak value of runoff in R. pseudoacacia stand was 10-20 min later than that in its clearcut area. Harmonic analysis of soil moisture dynamics indicated that the soil moisture in R. pseudoacacia stand was 2.3 % higher than that in clearcut area, and the soil moisture both in R. pseudoacacia stand and its clearcut area could be divided into dry season and humid season and varied periodically with annual rainfall precipitation. It was concluded that R. pseudoacacia stand plays a very important role in storing water, increasing soil moisture, and reducing surface runoff and soil erosion.

The value of toxicological analysis in acute poisoning patients with uncertain exposure histories:a retrospective and descriptive study from an institute of poisoning

BACKGROUND:In clinical practice,some patients might not be able or unwilling to provide a thorough history of medication and poison exposure.The aim of this study was to use toxicological analysis to examine the clinical characteristics of patients with acute poisoning whose exposure history was uncertain from a toxicological analysis perspective.METHODS:This was a retrospective and descriptive study from an institute of poisoning.Patient registration information and test reports spanning the period from April 1,2020 to March 31,2022,were obtained.Patients with uncertain exposure histories and who underwent toxicological analysis were included.Clinical manifestations and categories of toxics were analyzed.RESULTS:Among the 195 patients with positive toxicological analysis results,the main causes of uncertain exposure history was disturbance of consciousness(62.6%),unawareness(23.6%)and unwillingness or lack of cooperation(13.8%).The predominant clinical manifestations were disturbed consciousness(62.6%),followed by vomiting and nausea(14.4%)and liver function abnormalities(8.7%).A comparison of clinical manifestations between patients with positive and negative(n=99)toxicological analyses results revealed significantly different proportions of disturbances in consciousness(63%vs.21%),dizziness(1.5%vs.5.1%),multi-organ failure(1.5%vs.7.1%),and local pain(0 vs 4%).The main categories of substances involved were psychiatric medications(23.1%),sedatives(20.5%),insecticides(13.8%),and herbicides(12.8%).CONCLUSION:The clinical manifestations of acute poisoning in patients with an uncertain exposure history are diverse and nonspecific,and toxicological analysis plays a pivotal role in the diagnosis and differential diagnosis of such patients.

Computer vision-aided DEM study on the compaction characteristics of graded subgrade filler considering realistic coarse particle shapes

The compaction quality of subgrade filler strongly affects subgrade settlement.The main objective of this research is to analyze the macro-and micro-mechanical compaction characteristics of subgrade filler based on the real shape of coarse particles.First,an improved Viola-Jones algorithm is employed to establish a digitalized 2D particle database for coarse particle shape evaluation and discrete modeling purposes of subgrade filler.Shape indexes of 2D subgrade filler are then computed and statistically analyzed.Finally,numerical simulations are performed to quantitatively investigate the effects of the aspect ratio(AR)and interparticle friction coefficient(μ)on the macro-and micro-mechanical compaction characteristics of subgrade filler based on the discrete element method(DEM).The results show that with the increasing AR,the coarse particles are narrower,leading to the increasing movement of fine particles during compaction,which indicates that it is difficult for slender coarse particles to inhibit the migration of fine particles.Moreover,the average displacement of particles is strongly influenced by the AR,indicating that their occlusion under power relies on particle shapes.The dis-placement and velocity of fine particles are much greater than those of the coarse particles,which shows that compaction is primarily a migration of fine particles.Under the cyclic load,the interparticle friction coefficientμhas little effect on the internal structure of the sample;under the quasi-static loads,however,the increase inμwill lead to a significant increase in the porosity of the sample.This study could not only provide a novel approach to investigate the compaction mechanism but also establish a new theoretical basis for the evaluation of intelligent subgrade compaction.

Analysis of the Clinical Characteristics and Antibiotics Resistance of Community-acquired Methicillin-resistant Staphylococcus aureus

The purpose of this investigation is to study the clinical characteristics of infections by community-acquired methicillin-resistant Staphylococcus aureus (MRSA) and the condition of antibiotics resistance of the clinical isolates in order to guide for the rational use of antibiotics. With the clinical isolates from cases of hospital-acquired MRSA at the same period as controls, the clinical characteristics of infections by community-acquired MRSA in Hangzhou area and the pattern of non-β-lactamase antibiotics resistance were determined in this study. It was found that the average age of patients with community-acquired MRSA infections was 30.89±13.3, in comparison with those of the hospital-acquired patients of 56.0±11.8, appearing to be younger than those of the latter, and the former showing no any basic illness. Both of the former and the latter were sensitive to vancomycin (100% vs 100%), and they had the same degrees of sensitivity to rifampicin, fosfomycin, and STM/TMP (86.8% vs 88.1%, P >0.05; 81.6% vs 82.9%, P >0.05; and 52.6% vs 61.9%, P >0.05, respectively). The former was more sensitive to netimycin, clindamycin, erythromycin and minocycline than those of the latter (73.7% vs 50.5%, P <0.01; 60.5% vs 45.7%, P <0.05; 28.9% vs 11.4%, P <0.01; and 81.6% vs 58.6%, P <0.01 respectively). Meanwhile, the incidence of multi-resistant strain of isolates in the former was significantly lower than that of the latter (31.6% vs 81.0%, P <0.01). In conclusion, it appears that the strains of clinical isolates isolated from patients with the community-acquired MRSA infections show different clinical characteristics and antimicrobial susceptibility in comparison with those of the hospital-acquired cases of infection, and this necessitates an alteration in the chemotherapy of infections suspected to be caused by community-acquired MRSA.

Analysis and verification of electrodynamic force,thermal stress and current sharing for CRAFT converter structure design

In the design realm of fusion power supplies,structural components play a pivotal role in ensuring the safety of fusion devices.To verify the reliability of the converter structure design at the Comprehensive Research Facility for Fusion Technology(CRAFT),meticulous analysis of the converter's dynamic impact is carefully performed based on the worst fault current(400k A),firstly.Subsequently,the thermal stress analysis based on the maximum allowable steadystate temperature is finished,and the equivalent thermal stress,thermal deformation,maximum shear stress of a single bridge arm and the whole converter are studied.Furthermore,a simple research method involving the current-sharing characteristics of a bridge arm with multithyristor parallel connection is proposed using a combination of Simplorer with Q3D in ANSYS.The results show that the current-sharing characteristics are excellent.Finally,the structural design has been meticulously tailored to meet the established requirements.

Network analysis of the relationships between depressive symptoms and social participation activities among Chinese older adults and its implications for nursing

Objective:Network analysis was used to explore the complex inter-relationships between social participation activities and depressive symptoms among the Chinese older population,and the differences in network structures among different genders,age groups,and urban-rural residency would be compared.Methods:Based on the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey(CLHLS),12,043 people aged 65 to 105 were included.The 10-item Center for Epidemiologic Studies Depression(CESD)Scale was used to assess depressive symptoms and 10 types of social participation activities were collected,including housework,tai-chi,square dancing,visiting and interacting with friends,garden work,reading newspapers or books,raising domestic animals,playing cards or mahjong,watching TV or listening to radio,and organized social activities.R 4.2.1 software was used to estimate the network model and calculate strength and bridge strength.Results:21.60%(2,601/12,043)of the participants had depressive symptoms.The total social participation score was negatively associated with depressive symptoms after adjusting for sociodemographic factors.The network of social participation and depressive symptoms showed that“D9(Inability to get going)”and“S9(Watching TV and/or listening to the radio)”had the highest strength within depressive symptoms and social participation communities,respectively,and“S1(Housework)”,“S9(Watching TV and/or listening to the radio)”,and“D5(Hopelessness)”were the most prominent bridging nodes between the two communities.Most edges linking the two communities were negative.“S5(Graden work)-D5(Hopelessness)”and“S6(Reading newspapers/books)-D4(Everything was an effort)”were the top 2 strongest negative edges.Older females had significantly denser network structures than older males.Compared to older people aged 65e80,the age group 81e105 showed higher network global strength.Conclusions:This study provides novel insights into the complex relationships between social participation and depressive symptoms.Except for doing housework,other social participation activities were found to be protective for depression levels.Different nursing strategies should be taken to prevent and alleviate depressive symptoms for different genders and older people of different ages.

Clinical characteristics of patients with early gastric prematurity cancer and analysis of complications by endoscopic resection

BACKGROUND Gastric cancer,a prevalent malignancy,poses a severe threat to the health of residents in China.Timely intervention in early stages can extend patients’survival.AIM To analyze clinical characteristics of patients with early gastric cancer and efficacy and risk of complications associated with endoscopic resection.METHODS This study included 175 patients with early gastric cancer treated at our hospital,with no restrictions on sex or age.General data,pathological information,and endoscopic biopsy results were obtained.The clinical characteristics of early gastric cancer were analyzed,and endoscopic resection was performed.Postoperative efficacy and incidence of complications were monitored.Statistical analysis was performed using SPSS 26.0 and GraphPad Prism 8.0 software.RESULTS A total of 175 patients with early gastric cancer were included,with 75.43%(n=132)males and 24.57%(n=43)females.38.29%(n=67)and 35.43%(n=62)of patients had a history of smoking and alcohol consumption,respectively.Comorbidities included diabetes(8.57%,n=15),coronary heart disease(10.29%,n=18),and hypertension(43.43%,n=76),which was highly prevalent.A history of abdominal surgery and family history of digestive system cancer accounted for 21.14%and 17.14%,respectively.The most common lesion location was the antral part of the stomach(52.00%,n=91),followed by the gastric angle,body,and fundus.The pathological types were predominantly high-grade intraepithelial neoplasia(28.00%,n=49)and well-differentiated adenocarcinoma(26.86%,n=47),followed by moderately differentiated adenocarcinoma,high-moderately differentiated adenocarcinoma,and moderate-lowly differentiated adenocarcinoma.89.14%of the patients had intestinal metaplasia and 85.14%had atrophy.After endoscopic resection,re-examination revealed that 13 patients had cancer cells at the tissue margin,with a positive margin rate of 7.43%.Postoperative complications included no cases of gastrointestinal obstruction,but incisional infection(2.86%,n=5),gastric perforation(1.14%,n=2),and gastric bleeding(4%,n=7)were present,with an overall incidence of 8.00%.CONCLUSION Analysis of the clinical characteristics indicated that early gastric cancer is more prevalent in males with a history of hypertension,with lesions most commonly occurring in the antral region of the stomach.The pathological types are often high-grade intraepithelial neoplasia and well-differentiated adenocarcinoma,with over 85%of patients having comorbid intestinal metaplasia and atrophy.Despite endoscopic resection,a positive margin rate persisted,indicating a probability of residual cancer at the margins.Postoperative complications,such as gastrointestinal obstruction,incisional infection,gastric perforation,and gastric bleeding can occur and require timely symptomatic treatment.

Effect of cyclic hydraulic stimulation on pore structure and methane sorption characteristics of anthracite coal: A case study in the Qinshui Basin, China

The cyclic hydraulic stimulation(CHS) has proven as a prospective technology for enhancing the permeability of unconventional formations such as coalbeds. However, the effects of CHS on the microstructure and gas sorption behavior of coal remain unclear. In this study, laboratory tests including the nuclear magnetic resonance(NMR), low-temperature nitrogen sorption(LTNS), and methane sorption isotherm measurement were conducted to explore changes in the pore structure and methane sorption characteristics caused by CHS on an anthracite coal from Qinshui Basin, China. The NMR and LTNS tests show that after CHS treatment, meso- and macro-pores tend to be enlarged, whereas micropores with larger sizes and transition-pores may be converted into smaller-sized micro-pores. After the coal samples treated with 1, 3, 5 and 7 hydraulic stimulation cycles, the total specific surface area(TSSA)decreased from 0.636 to 0.538, 0.516, 0.505, and 0.491 m^(2)/g, respectively. Fractal analysis based on the NMR and LTNS results show that the surface fractal dimensions increase with the increase in the number of hydraulic stimulation cycles, while the volume fractal dimensions exhibit an opposite trend to the surface fractal dimensions, indicating that the pore surface roughness and pore structure connectivity are both increased after CHS treatment. Methane sorption isothermal measurements show that both the Langmuir volume and Langmuir pressure decrease significantly with the increase in the number of hydraulic stimulation cycles. The Langmuir volume and the Langmuir pressure decrease from 33.47 cm^(3)/g and 0.205 MPa to 24.18 cm^(3)/g and 0.176 MPa after the coal samples treated with 7 hydraulic stimulation cycles, respectively. The increments of Langmuir volume and Langmuir pressure are positively correlated with the increment of TSSA and negatively correlated with the increments of surface fractal dimensions.

Analysis on Clinical Characteristics and Combination Medications of Elemene Injection in the Treatment of Esophageal Cancer in Real World Research

Objective:To explore the clinical characteristics of Elemene Injection in the treatment of patients with esophageal cancer.Methods:A total of 310 patients diagnosed with esophageal cancer from the Hoptital Information System(HIS)of 21 hospitals across the country were selected in the study,and these patients all had been treated with Elemene Injection.In this study,the clinical general medication record information,diagnosis scheme information,general treatment information and combined medications information were analyzed by frequency statistics and association rules.Results:Elemene Injection was used most in patients aged 46-65(177 cases,57.10%);male patients were more than female.Among the main diagnoses of the most seasons and solar terms in hospitalization,the top three diagnoses were esophageal malignant tumor,malignant tumor,and hypertension.In terms of combination medication,the combination of western medicine blood substitutes and perfusion fluids,general nutritional drugs,vitamins,antibacterial drugs,and immune-promoting drugs were the main ones;the combination of traditional Chinese medicine was mainly anti-tumor drugs(48.71%).In addition,among the combination medications,the highest frequency of Elemene Injection combined with western medicine and traditional Chinese medicine were Xiaoaiping Injection(消癌平注射液)and ascorbic acid.Conclusion:The main susceptible people of esophageal cancer was middle-aged around 46-65,and there were more male patients than female;through the first diagnosis of western medicine,it can be found that in addition to patients suffering from esophageal cancer or other cancers,patients with high blood pressure,heart disease,and diabetes could use Elemene Injection.Therefore,when receiving such patients,attention should be paid to checking whether the patient had such diseases.At the same time,when using Elemene Injection,it's necessary to pay attention to certain combined medications to avoid adverse reactions.

Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron

Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements affecting the solidification of molten iron.In this study,FeSi75 was added in one chamber of the dual-chamber sample cup,and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were investigated.The results show that with the increase of FeSi75,the start temperature of austenite formation TALfirstly decreases and then increases,but the start temperature of eutectic growth TSEF,the lowest eutectic temperature TEU,temperature at maximum eutectic reaction rate TEM,and highest eutectic temperature TERkeep always an increase.The temperature at final solidification point TEShas little change.The FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation,and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher one.According to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.%FeSi75 additive in one chamber,the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these curves.The time differenceΔtERcorresponding to the highest eutectic temperature TERhas a closer relationship with the vermiculating rate,and a parabolic regression curve between the time differenceΔtERand vermiculating rateηhas been obtained within the range of 65%to 95%,which is suitable for the qualified melt.

Application of modified discontinuous deformation analysis to dynamic modelling of the Baige landslide in the Jinsha River

Accurate dynamic modeling of landslides could help understand the movement mechanisms and guide disaster mitigation and prevention.Discontinuous deformation analysis(DDA)is an effective approach for investigating landslides.However,DDA fails to accurately capture the degradation in shear strength of rock joints commonly observed in high-speed landslides.In this study,DDA is modified by incorporating simplified joint shear strength degradation.Based on the modified DDA,the kinematics of the Baige landslide that occurred along the Jinsha River in China on 10 October 2018 are reproduced.The violent starting velocity of the landslide is considered explicitly.Three cases with different violent starting velocities are investigated to show their effect on the landslide movement process.Subsequently,the landslide movement process and the final accumulation characteristics are analyzed from multiple perspectives.The results show that the violent starting velocity affects the landslide motion characteristics,which is found to be about 4 m/s in the Baige landslide.The movement process of the Baige landslide involves four stages:initiation,high-speed sliding,impact-climbing,low-speed motion and accumulation.The accumulation states of sliding masses in different zones are different,which essentially corresponds to reality.The research results suggest that the modified DDA is applicable to similar high-level rock landslides.

Research on the Stability Analysis Method of DC Microgrid Based on Bifurcation and Strobe Theory

During the operation of a DC microgrid,the nonlinearity and low damping characteristics of the DC bus make it prone to oscillatory instability.In this paper,we first establish a discrete nonlinear system dynamic model of a DC microgrid,study the effects of the converter sag coefficient,input voltage,and load resistance on the microgrid stability,and reveal the oscillation mechanism of a DC microgrid caused by a single source.Then,a DC microgrid stability analysis method based on the combination of bifurcation and strobe is used to analyze how the aforementioned parameters influence the oscillation characteristics of the system.Finally,the stability region of the system is obtained by the Jacobi matrix eigenvalue method.Grid simulation verifies the feasibility and effectiveness of the proposed method.

Clinical characteristics and risk factors of post-operative intestinal flora disorder following laparoscopic colonic surgery:A propensityscore-matching analysis

BACKGROUND Intestinal flora disorder(IFD)poses a significant challenge after laparoscopic colonic surgery,and no standard criteria exists for its diagnosis and treatment.AIM To analyze the clinical features and risk factors of IFD.METHODS Patients with colon cancer receiving laparoscopic surgery were included using propensity-score-matching(PSM)methods.Based on the occurrence of IFD,patients were categorized into IFD and non-IFD groups.The clinical characteristics and treatment approaches for patients with IFD were analyzed.Multivariate regression analysis was performed to identify the risk factors of IFD.RESULTS The IFD incidence after laparoscopic surgery was 9.0%(97 of 1073 patients).After PSM,97 and 194 patients were identified in the IFD and non-IFD groups,respectively.The most common symptoms of IFD were diarrhea and abdominal,typically occurring on post-operative days 3 and 4.All patients were managed conservatively,including modulation of the intestinal flora(90.7%),oral/intravenous application of vancomycin(74.2%),and insertion of a gastric/ileus tube for decompression(23.7%).Multivariate regression analysis identified that preoperative intestinal obstruction[odds ratio(OR)=2.79,95%CI:1.04–7.47,P=0.041]and post-operative antibiotics(OR=8.57,95%CI:3.31–23.49,P<0.001)were independent risk factors for IFD,whereas pre-operative parenteral nutrition(OR=0.12,95%CI:0.06–0.26,P<0.001)emerged as a protective factor.CONCLUSION A stepwise approach of probiotics,vancomycin,and decompression could be an alternative treatment for IFD.Special attention is warranted post-operatively for patients with pre-operative obstruction or early use of antibiotics.

Clinical characteristics and north-south differences of inflammatory bowel disease in China: A cross-sectional study and meta-analysis

Objective:This study aimed to estimate the incidence rate and clinical characteristics of inflammatory bowel disease(IBD)in the Chinese population,specially comparing the North and South regions.Methods:We designed a questionnaire survey for patients diagnosed with IBD and conducted a systematic literature search in PubMed,China National Knowledge Internet,and Wanfang digital database,covering studies published between 2012 and 2022.Meta-analysis was performed to determine the overall incidence rate and prevalence of clinical manifestations of Crohn's disease(CD)and ulcerative colitis(UC)in China's Mainland.Clinical phenotypes and demographic characteristics were calculated with 95%confidence intervals(CI).A comparison between the northern and southern regions was also conducted.Results:The questionnaire survey included 440 patients,and 64 publications were included for Meta-analysis.The overall incidence rates of IBD,CD,and UC were 1.36(95%CI:0.79-2.33)per 100,000 person-years,0.23(95%CI:0.09-0.58)per 100,000 person-years,and 1.12(95%CI:0.69-1.80)per 100,000 person-years,respectively.The incidence rates of IBD,CD,and UC were all higher in southern China compared to the North.Clinical characteristics of 440 IBD patients from the questionnaire and 2,821 CD patients and 12,809 UC patients from the literature were analyzed.There were more male patients compared to female patients.CD cases in the North exhibited earlier disease diagnosis(P<0.01),more upper gastrointestinal lesions(P<0.01),and higher hospitalizations rates(P<0.01)compared to the South.UC cases in the North had higher severity(P<0.01),anemia rates(P<0.01),and weight loss(P<0.01)compared to the South.Conclusions:The incidence rates of IBD,CD,and UC were higher in southern China than in the North.Northern patients exhibited more severe symptoms compared to their southern counterparts.